The Flash: Everything you need to know about Flashpoint

Thought The Flash's season 2 finale, which saw Barry Allen (Grant Gustin) change the series’ entire timeline by saving his mother’s life, was nuts? Well, the butterfly effects of that choice are about to get even weirder — as fans of The Flash comic well know.

In the comics, the twisty, seminal Flashpoint story line finds Barry in an alternate world where his mother is no longer dead and most of the world’s heroes are more like villains — Aquaman is at war with Wonder Woman, Batman is Thomas Wayne, not his son Bruce, and Captain Cold is Central City's savior Citizen Cold.

Unlike the global scale of the comic, though, the CW series is taking a more personal approach to the changes Barry has wrought. "All of that stuff is not at our disposal, which is fine with us, because we really wanted to do something personal to Barry," executive producer Andrew Kreisberg tells EW. "The stakes in the comic book in Flashpoint were global and the stakes in this episode are very much just about Barry, his existence, and the people that he loves." (Though, Flashpoint will spill over in a very specific way on Arrow with David Ramsey's Diggle.)

Three months have passed since Barry's fateful decision to save his mother from being killed by the Reverse-Flash (Matt Letscher). He's been living in bliss with his mother Nora (Michelle Harrison) and father Henry (John Wesley Shipp), both of whom are dead in the original timeline. "He’s actually in a happy place, which is somewhere you don’t always see Barry Allen in," Kreisberg says. "He’s now living in a world where his mother is alive and he’s taking it as, 'I’ve finally got my reward for all of the suffering that I’ve gone through. This is my prize.'"

Image Credit: Katie Yu/The CW

And while that's quite the drastic change for Barry, the Flashpoint timeline itself "looks like our world," Kreisberg says. "Most of the changes are to Barry’s life and him being at the nexus of these changes. He’s put all of the people that are in his life — Joe [Jesse L. Martin], Iris [Candice Patton], Cisco [Carlos Valdes], and Caitlin [Danielle Panabaker] — and spun them into different ways."

For example, Barry may still have his powers, but he's no longer a hero, replaced by new speedster Kid Flash (Keiynan Lonsdale). "We wanted to do something bold and start the season off with a bang," Kreisberg says. "So we decided to get Wally in the suit. The circumstances of how that happens, well, you’ll have to watch to see."

Barry's former allies also don't even know him. Joe, for one, struggles in his own relationship with his daughter Iris. "In some ways, Barry has sacrificed his relationship with Joe for his relationship with his birth family, and that’s one of the challenges that Barry has to overcome in the episode," Kreisberg teases. But that also means Barry has a clean slate with Iris and can actually woo her. "Barry says in the episode, 'Iris is always Iris,'" Kreisberg notes. "So their relationship and their connection seems to be able to survive any changes to the timeline or any universe. There’s always something between them."

Cisco, meanwhile, is now an ostentatious billionaire running apparent S.T.A.R. Labs replacement Ramon Industries. "It was something we talked about doing for Earth-2 with Cisco, that he was rich and a billionaire," Kreisberg says. "We just had a lot of fun with the idea of seeing that version of the character. We learned a lot last season doing Earth-2 and watching the dichotomy between the characters, especially watching how different they could be, and having such an amazingly talented cast that can pull off multiple versions of these characters. It’s just always fun to have Barry have to interact with different versions of the people that he knows well, because the audience knows them so well. A selfish, rich, cowardly Cisco couldn’t be further from the Cisco that we all know and love."

For Caitlin and Harry (Tom Cavanagh), though, Kreisberg plays mum on how they're different — a running theme each season for the latter. "I don’t want to get too much into the specifics of it, because that’s part of the fun of going through this journey to Oz with these characters," Kreisberg says. "The audience is discovering as they watch it what’s different and what’s the same." However different these characters may be, “Part of Barry’s journey is getting these people, who aren’t necessarily the best version of themselves, to find their inner hero,” Kreisberg says of all the former Team Flash members.

Image Credit: Katie Yu/The CW

Barry’s decision will also ultimately bring two new villains into the fray: the yet-to-be-cast Doctor Alchemy and speedster Savitar. "We’re so excited about the dynamic between the villains and their dynamic with Flash, and the rest of the team," Kreisberg says, teasing that Doctor Alchemy's agenda is tied into the other villains, plural. "We really want to play cards down for now, because the surprises are going to be worth the wait."

The current prevailing theory is that new cast member Tom Felton, who joins the show as CSI Julian Dorn, is actually Doctor Alchemy — he comes on as Barry's nemesis at work in this new timeline. The duo have been sharing workspace for the last year and Julian "definitely treads on the toes of Barry's expertise," Felton says.

But Kreisberg, again, is staying mum, instead praising Felton's addition to the cast. "We’ve obviously always been fans of Tom’s," he says of casting the Harry Potter alum. "We’ve all seen him grow up from an amazing child actor to an amazing adult actor. Season threes are typically when you add that character that comes in to shake things up, just in the same way we added Brandon Routh to Arrow in season 3. Having Tom join the show and adding his energy, his delivery, and his performance to our very tightly knit cast is definitely meant to help shake things up."

Image Credit: Katie Yu/The CW

The Flashpoint timeline will also welcome back a familiar face, Reverse-Flash, who will serve as Barry’s conscience. "Barry has messed with the universe to find his happy ending and he’s put in the awkward and ironic position of having his greatest villain, the man who killed his mother, being the one to tell him, 'This is wrong, you’re a hero and heroes don’t do this,'" Kreisberg says. "It’s a great way to have him interact with his singular greatest foe by having the villain essentially be on the side of the angels and be right."

And while the show may be going micro when it comes to Flashpoint, fans of the source material will still be delighted by the Easter eggs throughout. "There’s a couple of nods to the comics in there," Kreisberg says. "There’s actually some dialogue from the comic in the episode. But as always, the movies are the movies and TV is TV, and we’re not trying to infringe on their purview."

Kreisberg also reveals that there’s a ticking clock on Flashpoint as Barry’s memories of the old timeline begin to be replaced by the new, forcing him to make a big choice. “We are going to see him start to have some regrets and realize how selfish of a decision it was [to save his mom],” Gustin says. Kreisberg adds that Barry will be "coping with [the fact that] he may have traded his happiness for his friends. He begins to see that the cost of him getting his happy ending might be too much to bear."

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With that in mind, the Flashpoint storyline is not expected to last long, but it will leave a lasting impression. "It will be resolved, but there will be consequences that last throughout the season, and quite frankly, last throughout the series," Kreisberg says. "That’s one of the things that we’re attempting to do is have the pitfalls of time travel be long-lasting and that some things can be fixed, and then some things are broken forever."

The Flash returns Tuesday, Oct. 4 at 8 p.m. ET on The CW.